Everything depends on which ACME client you're using. There's no technical limitation from Let's Encrypts end, but your ACME client may or may not support re-keying and/or multiple ACME accounts.
Everything depends on which ACME client you're using. There's no technical limitation from Let's Encrypts end, but your ACME client may or may not support re-keying and/or multiple ACME accounts.